1. Field of the Invention
The present invention relates generally to detection of radiation threat materials within shipping containers and, more particularly, to improvements to a spreader or hoist attachment of a container crane wherein such improvements are used for the non-invasive and passive collection of radiation data from a container engaged thereto and transmission of such data.
2. Description of the Related Art
On Sep. 11, 2001, coordinated terrorist attacks on the New York World Trade Center and on the Pentagon utilized hijacked commercial aircraft as the transport mechanism for incendiary devices, i.e., the very fuel tanks of the hijacked aircraft themselves. Upon these aircraft being deliberately crashed into these structures, their fuel tanks explosively ruptured to disperse ignited jet fuel resulting in the tragic loss of thousands of lives and total destruction of the World Trade Center Twin Towers.
These terrorist attacks have renewed defense awareness that the common transport systems of global commerce can be surreptitiously used as weapons delivery systems, particularly when such systems transport smuggled weaponry triggered to detonate when the transport device is near or arrives at an intended target. In particular, a grave concern is that radioactive weapons, which spread radioactive contamination over a relatively small area through conventional explosives, and nuclear weapons, which cause widespread destruction through the spontaneous release of high fission or fusion energy from a nuclear core, may be surreptitiously smuggled from abroad in shipping containers and detonated at the port of entry, or later when the still sealed shipping container has been transported by rail or truck to a populated inland destination.
The threat of any of these types of weapons being smuggled into a country from a foreign territory and then being detonated has been recognized since the dawn of the atomic age. In his famous letter of Aug. 2, 1939, Albert Einstein warned President Franklin Roosevelt that “(a) single bomb of this (nuclear) type, carried by boat and exploded in a port, might very well destroy the whole port together with some of the surrounding territory.”
Although the threat of smuggled nuclear weapons, as foreseen by Einstein, has long been known, it was mitigated by the fact that ten years following Einstein's letter only a few of the most militarily powerful nations possessed nuclear weapon capability. The threat was further overshadowed by the more efficient long range bomber delivery and the later developed intercontinental ballistic missile delivery systems for such weapons, which through multiple simultaneous launches could deliver an almost instantaneous fatal blow to one's adversary.
Because the Cold War antagonists and their respective allies possessed symmetry in nuclear weaponry and delivery systems, the totality of the retaliatory response to be wreaked upon the aggressor first to use of such weapons resulted in the doctrine of mutually assured destruction. Under this doctrine, the initial use of a nuclear weapon through any means of delivery, even if confined to a single nuclear weapon, would be responded to with the same retaliatory response of absolute destruction to be wreaked upon the aggressor as if the initial attack was devised to deliver a fatal blow. The secondary attack in response to the retaliatory response would thus also require absolute destruction to be wreaked upon the responder to the initial attack. Thus, nuclear warfare between the Cold War antagonists was not devised to be waged symmetrically in limited tit for tat engagements thereby ensuring that even the limited use of nuclear weapons was not a viable military option.
Since the ostensible end to the Cold War, the greatest threat to the current world order is an asymmetrical one from non-state aligned terrorists, self-described as jihadists who ascribe to a nihilistic Islamic ideology, and their state sponsors. The jihadists seek through terror to cause the destruction of the nation-state economic and political order and, with the intent of global domination, to revive the Islamic caliphate, which had last been defeated in World War I and replaced by the Kemalists in Anatolia and the current nation states of the Levant and Mesopotamia.
Because such ideology is nihilistic, death to its adherents is of minimal consequence and even, at times, celebrated as long as it advances the jihadist's cause. Furthermore, the jihadists are widely dispersed and do not operate on a centralized command and control hierarchy, but operate mostly from localized cells, which through a shared ideology and use of terror as a means to achieve an end unite these cells into a global force. Moreover, the cells themselves may often be embedded in the very civilian populations they seek to terrorize. Accordingly, the threat of overwhelming retaliatory force is of little or no deterrent effect to the jihadist, thereby rendering the threat asymmetrical.
Asymmetrical warfare does not depend upon the widespread or total military destruction of the nation state. For example, a coordinated jihadist attack on just a few hubs of the global transport systems through the use of radioactive weapons, although not causing extensive loss of life or physical damage to these and their related structures, would render these hubs unusable for several years through the spread of radioactive contamination. Major disruptions in the flow of international commerce would result from such an attack, causing a global economic slowdown, if not global economic depression, thereby resulting in increased local and global political instability.
In response to this asymmetrical threat, the transport mechanisms of global commerce have recently been subject to increased monitoring and stringent security measures to minimize the chances of a radioactive weapon or nuclear device being successfully smuggled. However, one of the major problems of increased monitoring is that such monitoring may significantly overburden and substantially slow the flow of commerce. Since the rapid movement of freight is the hallmark of global commerce, a substantial slowdown in freight handling just through increased inspections partially achieves the aims of the terrorist even if no weapons were smuggled. Terrorists are cognizant of the fact that just the threat of terror causes economic disruption.
One of the basic transport mechanisms of the modern global economy is containerized shipping. Because goods move rapidly in global commerce, shipping containers have unfetteredly moved in and out of the seaports of the world with little or no inspection of their contents. For example, in 2003, the United States Government admitted that ninety-five percent (95%) of the some 30,000 shipping containers that entered U.S. ports every day were not inspected in any way. Introduced on Nov. 15, 2005, U.S. Senate Bill S.2008 stipulates that, of those containers identified by U.S. Customs and Border Protection's (“CBP's”) profiling system as “high risk,” less than 18% were inspected in any way.
This lack of inspection and consequent risk of nuclear smuggling extends in even greater percentages to the some 300 million shipping containers that move in and out of the ports, and over the roads and rails, of the nations of the world every year. Since shipping containers could be the transport system of choice for smuggled radiation weapons and nuclear devices, effective, broad based inspection of shipping containers is urgently required.
The surest way to prevent smuggling of radiation and nuclear weapons is physically to open and inspect each and every shipping container as it moves through all of the major transit points, that is, at each seaport, airport and border-crossing. However, it should be obvious that such large scale, invasive inspections are not economically feasible. Such rigorous inspections would result in global shipping effectively grinding to a halt because of the inability of shipping containers to pass through points of entry. The aforementioned economic disruption and instability would result from such inspections being rigorously carried out, thereby achieving the very goal of the terrorists without any weapon even being present.
To overcome the unfeasibility of physically inspecting each and every shipping container, various active and passive radiation detection systems for shipping containers have been proposed that enable containers to be inspected while in transport. For example, in the '421, '944 and '235 patents, various passive radiation detection methods and apparatus are disclosed for the non-invasive “on the fly” inspection of shipping containers.
a. Passive Versus Active Radiation Detection Devices
Both radioactive and nuclear weapons contain radioactive or fissile material. As is known, this radioactive material spontaneously emits radiation. This radiation occurs either directly from unstable atomic nuclei or as a consequence of a nuclear reaction. It comprises alpha particles, nucleons (protons and neutrons), electrons and gamma rays. As disclosed in the '421, '944 and '235 patents, this radiation can be detected by using non-invasive passive detection systems and methods.
Non-invasive passive detection systems and methods are to be distinguished from non-invasive active detection systems and methods. The critical distinguishing factor is that passive systems and methods utilize radiation that is naturally emitted from materials. Active systems and methods create a source of radiation which itself emits harmful radiation.
In an exemplary active system, a source of radiation, exemplarily gamma or neutron radiation, is aimed at the container and its contents. The radiation passes through the walls of the container and interacts with its contents. Specifically, the radiation is absorbed by the contents, such that each item of the contents of the container then gives off further gamma radiation at an energy level characteristic for each item. From a scan of the energy peaks, it can be determined if any one peak is associated with a known energy peak of a radioactive material. An active scanning system, similar to as just described, is disclosed in Armistead, U.S. Pat. No. 5,838,759.
There are serious medical, moral, legal and economic considerations in the use of active systems and methods. First, the source of radiation is carcinogenic and dangerous to the health and safety of workers who operate and work in the immediate area of the system. In June of 2005, the National Academy of Sciences issued a long awaited report on the biologic effects of ionizing radiation entitled “BEIR: VII Health Risks from Exposure to Low Levels of Ionizing Radiation.” It states: “A comprehensive review of available biological and biophysical data supports a ‘linear-no-threshold’ (LNT) risk model—that the risk of cancer proceeds in a linear fashion at lower doses without a threshold and that the smallest dose has the potential to cause a small increase in risk to humans.” Second, the operators of active systems face long term legal liability exposure much the same as asbestos manufacturers did in the 1970s, 1980s and 1990s. And third, organized labor and dock workers (longshoremen and teamsters) will often refuse to work around active radiation systems thus stopping the work flow altogether.
On the other hand, passive systems and methods, of the type as disclosed in the '421, '944 and '235 patents, obviate the need for a separate source of radiation by measuring the radiation that is naturally emitted from the environment, the container and the contents of the container. If an anomaly from the normally existing radiation is detected, there is an indication that the container may contain radioactive material even if an attempt has been made to shield the presence of such radioactive material by use of a radiation absorbent material. More particularly, in the disclosed passive radiation detection devices (1) gamma rays emitted by radioactive or fissile material in a shipping container that exist about a shipping container are detected and counted (“gamma count”); (2) the energy level of those detected and counted gamma rays is measured (“gamma energy”); and, (3) neutrons emitted by radioactive or fissile material in a shipping container that exist about a container may also detected and counted (“neutron count”). As more fully described in the '421, '944 and '235 patents, these three data points, i.e., gamma count, gamma energy and neutron count, can be then used to analyze and determine, within acceptable limits, what radioactive material is inside a given shipping container or if radiation absorbent material is present possibly shielding radioactive material.
b. Crane-Mounted (Hoist Attachment or Spreader) Radiation Detection
The hallmark of containerization is the rapid movement of freight. Any additional operation that is performed during the movement of the container from shipper to consignee slows it down and creates inefficiency. But this rapid movement creates a plain and serious security risk. A balance between efficiency and security must be reached. To achieve the optimum balance, the radiation scanning should be in the normal workflow of the container. This means that the scanning activity should take place at the same time and place when and where the container would otherwise move.
As stated in the '421 patent, the principal time and place for radiation scanning to occur “when and where the container otherwise moves” are during the loading and unloading process by the container crane. During this process, hydraulically operated male pieces called “twist locks” at the four corners of the hoist attachment or spreader of the crane attach or lock into female fittings at the four corners of the shipping container called “corner castings.” In the vernacular of the art, “twist lock” is oftentimes used as the verb “to twistlock” and the spreader is then referred to as being “twistlocked onto the container.” While the hoist attachment or spreader is twistlocked onto the container, the container can be lifted and moved between ship and wharfage.
Typically, the hoist attachment or spreader is twistlocked onto the container for a time period between approximately 20 seconds and 100 seconds. Thus, very little time is required in the loading and unloading process, contributing to the rapid movement of freight. When the radiation sensors are located on all four sides and the center of the underneath of the hoist attachment or spreader, as described in the '421, '944 and '235 patents, then the sensors are stationary with respect to the container and its contents. Taking advantage of this relative stationary disposition between container and sensors for a time period of between 20 and 100 seconds, the apparatus and methods of the '421, '944 and '235 patents have been designed to scan and analyze containers that have been twistlocked so that there is no degradation in the transit time of the container.
Also, while a container has been twistlocked, the hoist attachment or spreader's main body comes within 6 to 18 inches from the top of the container. Since the height of the maritime shipping container is standardized at 8½ feet and 9½ feet, the distances between the sensors and the twistlocked container, and its contents, are within the detection range of the sensors so that the radiation about the container can be measured to determine, as disclosed in the '421, '944 and '235 patents, whether radioactive material or radiation absorbent material is present in the container. By taking advantage of the distances of the radiation sensors from the container while twistlocked, along with the time duration that such container is twistlocked, the apparatus and methods disclosed in the '421, '944 and '235 patents enable radiation scanning of a container while it is still in its normal workflow.
Contrary to the disclosures of the '421, '944 and '235 patents, highly placed, U.S. Government officials have stated that crane-mounted radiation detection “does not work” because the sensors cannot be sufficiently shock absorbed. On Oct. 24, 2004, the Deputy Administrator for Defense Nuclear Nonproliferation of the U.S. Dept. of Energy cast doubt on the possibility of a crane-mounted radiation detection system stating, among other things, “[T]he systems would have to be exceptionally robust to withstand the application there.”
During the loading and unloading process, the hoist attachment is brought into contact with, and twistlocked onto, the container. While twistlocked, the container is hoisted and put into place either onboard ship or dockside on the top wharfage whence the twistlocks are opened to release the hoist attachment from the container. During each of these actions, the hoist attachment is subject to impact, shock and vibrations from the forces of collisions that occur. Additionally, the accelerative forces during the loading and unloading process of the container place stresses and strains on the hoist attachment when it is twistlocked onto the container.
All of these various forces cause mechanical energy to be propagated through the hoist attachment. It has been found that this energy may be disruptive to the normal operation of the radiation sensors and may further cause their failure. Thus, although the systems and methods first described in the '412 patent have subsequently been built, tested and successfully demonstrated, a need arose for a radiation detection unit so that a radiation sensor can be mounted to a structure in which mechanical energy, otherwise disruptive to the operation of the radiation sensor, is propagated to the structure.
There are other advantages to crane-mounted (hoist attachment or spreader) radiation detection. The hoist attachment or spreader is the last piece of equipment to touch the container as it is hoisted from the wharfage and loaded onto the container ship at the originating port. The hoist attachment or spreader is also the first piece of equipment to touch the container upon arrival at the destination port. Crane-mounted (hoist attachment or spreader) radiation detection eliminates any shoreside opportunity to contaminate or compromise the container. Crane-mounted (hoist attachment or spreader) radiation detection does not use scarce terminal real estate in a wasteful, non-container-storage use. And lastly, crane-mounted radiation sensors experience varying levels of background radiation that provide additional data points from which to make content determinations.
In the event a container does contain a radioactive weapon or nuclear device that is triggered to detonate upon reaching a destination port with the intent of disabling such port, the detection systems of the '421, '944 and '235 patents, if employed only at the destination port, may not provide sufficient time to prevent the disaster from occurring should the threat be detected. Furthermore, the threat may have already been realized from detonation while the container containing the threat is still onboard the container ship prior to being scanned. As stated above, since the hoist attachment when twistlocked into a container is the last piece of equipment to touch the container when being loaded onto a ship, it is during the loading process that the scan for threat materials is preferably made to obviate the aforementioned possibility of the threat being realized at the destination port.
However, origination ports may be in countries that are hostile to the interest of the nation of the destination port, or even if each country has nominally friendly relations, the port employees may be infiltrated by terrorists or their sympathizers. Although, the country of the originating port may acquiesce to detection systems being installed at their ports for scanning of all outgoing containers through action of international treaties and protocols, the country of the originating port may not welcome or allow foreign inspection monitors to be present. Thus the possibility exists that the port employees of such country could compromise the scanning process and falsify the scan results to enable a container with threat materials to be loaded onto the ship. Accordingly, another need exists to be able to monitor remotely the scan results of containers during the loading process.